Speed regulator



Filed sept. 23.. 1939 G. E. HOWARD SPEED REGULATOR v S'Sheets-Sheet l Dec. 10Q 1940.

G. I z. HOWARD SPEED REGULATOR Filed sept. 2s, l1959 3 Sheets-Sheet 2 INVENT I R BY s f ATTORNEY? Dec. 10, 19,40. Q E HQWARD 2,224,600 .f

SPEED REGULATOR Filed Sept. 23, 19.? 9 3 Sheets-Sheet 3 INVENTOR ATTORNEY.

Patented Dec. I0, 1940 UNITED ASTATES PATENT oFFlcE While my invention is hereinafter described in connection with its use on a motor vehicle driven by an internal combustion engine, it is-useful also in controlling the speed of engines used otherwise than to drive vehicles.

'One type of governing device commonly employed in controlling the-speed of internal combustion engines utilizes the suction or reduced pressure in the intake manifold to operate a piston or the like, in one direction, againstthe tension of a spring; the piston in turn having connection with a throttle valve and moves the valve toward closed position when the suction reaches a predetermined degree. Another type commonly employed is amechanically-driven speed governor which exerts a pull or force proportionate to engine speed, 'and has connection with the throttle `valve to effect restriction of fuel ow to the engine when the speed exceeds a predetermined rate.

Neither'of these types of governor is satisfactory. The suction-operated governor responds primarily to load, and it controls the speed only because there is a relation between speed and manifold pressures at various loads. This relation is subject to wide variation. It is different with every engine and every carburetor, and it varies in the same engine and same carburetor, with every make of gasoline and with the temperature of the incoming air and with barometric changes that are due either to change in elevation or change in weather conditions. To get even these approximate results, a cam has to be used whose contour is different for each engine and carburetor.v These cams are designed for one speed, and any change in speed' setting over or under the speed for which the cam is designed results in further variation that is often very pronounced.' Suction governors ordinarily o vary 20%, and frequently more, which is a condition that makes them entirely impractical.

Again, governors of the suction type are subject to lag, because of the volume of air or fuel mixture in the intake manifold, which is of 45 such volume relative to the size of the governor cylinder and piston as to function somewhat as a reservoir, so that too great a period of time is often required before the changes in pressure conditions in the intake manifold can become ef- 50 fective to operate the governor piston. In other words, lag is the phenomenon that represents the delay that occurs between the changes in the speed that are due to changes in load, and the change in position of the valve that controls the 55 admission of fuel to the engine. The .lag in operation of the governor piston frequently results in swings or overrunning movements. of the piston and consequent movement of the throttle valve past the point it should occupy in order to supply fuel only in such quantity as will cors rect the change in speed and load.

As to the mechanically-actuated governors of the centrifugal or other types which act directly upon the throttle, there is frequently too sudden movement of the valve through movement lo of the governor under variation in engine speed, with the result that there is fluttering or jerky operation, which is hard on the machine and on the nerves of the driver. Stable governorspf the centrifugal type ordi- 15 narily require speed variations or range of speed of at least 10%; thus for a given governor setting the speed will be stabilized by the governor at` say 45 miles per hour under full load, and will be stabilized at 50 miles per hour underno load.

In the case of centrifugal governors and suction-operated governors, both commonly are mechanically connected to the throttle valve by use of links or levers.iand there is consequently a considerable amount of friction which will pre- '25 vent free operation of the governor, and as the frictional resistance is not always the same, there will be irregular variation in accuracy in the operation of the governors.

One advantage of using governors on motor` ve- 30 hicles is that they supposedly will automatically maintains the vehicle at a certain speed, thusre'- lieving the driver of nervous strain and exhaustion such as occurs when he endeavors to maintain the` vehicle speed by constantly watching the 35 speedometer and operating the throttle valve in accordance with changes in rate of speed. In the manual control of the vehicle over long distances, the operator also becomes tired through having to hold his foot constantly on the accelerator pedal.

While in the case of a vehicle having a speed governor and a hand throttle which may be set at an open position, the driver is relievedof nervous and physical exhaustion above referred to, he will not usually secure the best average vehicle speed. For example, if the legal speed limit is miles per hour, it will usually happen, with governors of the `types above referred to, that the driver will find he has averages considerably 50 less than 50 miles per hour, because of the fixed or irregular variations in governor operation. If he should set the governorat such a point as to insure an average speed of 50 miles Vper ho there would be many timeswhen the vehicle/ 2 would be travelling too far above the legal limit, which, while it wouldl compensate for Vperiods of lower speed,I would be objectionable. It would run 521/2 miles per hour or over at light loads and render the operator liable for law infraction. f

It is one purpose of my invention to provide a governor of such accuracy that it will maintain the vehicle speed at approximately the legal limit. without substantial variations above or below such limit, and with consequent greater mileage per hour, and of course without nervous and physical strain on the driver.

' Another object of my invention is to provide governing apparatus wherein the two types of governors referred to are combined to operate cooperatively, in such manner that there is a greater accuracy of control than is possible with a suction-operated governor, and wherein the rhythmic or uttering action incident to the use of mechanically-actuated governors alone is l avoided.

Another object of my invention is to provide a .governing apparatus of such form that change of a predetermined degree of engine speed will .render the suctional force in the intake manifold instantly effective to move the throttle valve, even though there has been no substantial change in pressure within the manifold.

A further object of my invention is to provide governing apparatus of such form wherein there is no substantial interference vwith governing operation, through frictional resistance.

Still another object of my invention is to provide meanswhereby the 'governor can quickly be .rendered inoperative'to limit vehicle speeds, as

when a quick'burstoflspeed is required by the vehicle operator in order to avoid an accident.

Briefly stated, my invention comprises a main. speed control element that is actuated through changes in pressure at the intake manifold, and the varying of the eectiveness of such governing device. by the use of a supplemental governing device which is directly responsive to changes in engine speed.

Referring further to the matter of maintaining high average speed without exceeding legal speed limits, about the best that can be done through purely manual control of the throttle valve vis within about 2% variation from the desired average speed, and to maintain such speed within the 2% variation referred to requires constant attention by the operator to the speedometer and throttle pedal, which is, of course, nerve-racking and tiresome. By the-use of my invention an average speed can automatically be maintained with considerably less than a 2% variation;

' Some of the forms' which my invention may takeare shown in the accompanying drawings wherein Figure 1 is a side view of an automobile engine equipped with my invention; Fig. 2 is an enlarged view of a portion of the structure of Fig. 1, partly in section; Fig. 3 is a sectional view, on an enlarged scale, of a portion'of the electrically-operated control apparatus of Fig. 1; FigA shows a modified form of the structure of Fig. 3; Fig. 5 show's a control device of the centrifugal governor type employed with my apparatus; Fig. 6 shows a control device responsive to pressure lfrom the water pump or the oil pump of a motor vehicle; Fig. 'I is a diagrammatic view showing a modified form of electrical apparatus for controlling the admission of air to the governor cylinder of Figs. 1 and 2, and Fig. 8 is a.

view showing a throttle-operating pedal of such form that it can be latched at its depressed pod- 2,224,eoo Y tion, and which can also be utilized to render the suction-operated governing device ineffective.

As shown in Figure 1, the apparatus includes various conventional parts such as an air cleaner 8;4 a choke valve 9; a carburetor I0; a throttle valve II and a fuel inlet passageway I2 leading to the intake manifold 1. A foot pedal I3, which may be of conventional form or constructed as shown in. Fig. 8, has link connection with a bell crank I4, that is in turn connnected to a link I5 that has connection with a rocker arm I6 which is loosely mounted on a shaft I1, that carries the throttle valve I I, as shownmore clearly in Fig. 2. It will be seen that when the foot pedal I3 is depressed, the link I5 will be thrust upwardly lto rock the arm I6 in a clockwise direction upon the shaft I1. A crank arm I 8 is keyed to the shaft I 'I and carries a pin or stud I9 that lies behind the rocker arm4 I6, as shown in Fig. 2. A tension spring 20 has connection with the crank arm I8 and is an anchored to an adjusting screw 2l,

whereby the tension of the spring 20 can be adjusted. When the arm I6 is moved away from the stud I9, throughdepression of the foot pedal, against the tensional force of a spring 22, the spring 2li will rock the shaft I1 to move the throttle valve II to'open position.

In order to control the extent of throttle opening under the tension of the spring 20, I provide a cam block 23 which is mounted on a bar 2l, one end o f which is supported by a guid'e block 25 and the other end of which has connection with a piston 26 that is contained within a cylinder 21.-

A pipe 28, provided with a hand valve 30, leads from the cylinder 21 to the intake line I2 at a point between the throttle and the engine, so that upon a predetermined reduction in pressure within the manifold 1, the piston 2B will be subjected to suctional force that tends to move it toward the right, and hence to bring the cam'block 23 into engagement with a roller 29 that is carried" by the lower end of the crank arm I8, so that if said suction exceeds a predetermined degree, as when `the engine is running at a speed which is too high, the block 23 will be drawn to the right, causing the shaft I1 and the throttle. valve II to be rocked toward closed position, in a counterclockwise direction. The movement of the piston 26 is against the compression of aspring 3|, the resistance of which is adjusted by means of a screw l2.

It will be seen that the cam block 23 is quite steeply inclined at that end which initially engages lthe crank roller 29 and for the remainder of its length is less sharply inclined. 'I'he cam block is constructed in this manner so as to impart a wider angular movement to the valve Il, for a given distance of piston travel, when the valve is at approximately its wide open position,

.than when the valve is adjacent to its closed posi- In other words, it is desired that for a given tional force at said speed, under load changes, I

provide means for modifying the eectiveness of the suctional force within the cylinder21, and to this end provide means 4actuated directly in relation to engine speed, for admitting air into the suction line 2l. so that the suctional force therein `-which will generate not too high, and so that there will be anincrease of suctional force in vthecylinder 21 when the engine speed exceeds a predetermined rate.

To this end I provide a pipe 33 that communicates with the chamber 34. The valve chamber 34 in turn communicates through a pipe-35 with the intake line, at a point between the carburetor and the throttle valve, and through a pipe 36 with the atmosphere or at a point in advance of -the choke valve 9. A valve 31 (Fig. 3) is provided within the valve chamber 34 to control ow oi air through the pipe 33 to the pipe 28. `It will be seen that when the valve 31 is in its lowered position, air will flow from the pipe 35 or the pipe 36, or both, to the pipe 33, and being more nearly at atmospheric pressure than the air within the pipe 28, will cause a reduction in suctional force on the piston 36. The lines 35 and 36 are controlled by hand valves 39 and 40 respectively, so that a mixture of fuel and air can be drawn from below the carburetor or outside air drawn from above the throttle valve.

The valve 31 is operated by a solenoid 4| which is energized by a generator 42. 'I'he generator 42 is driven by the fan belt 43 or some other moving part of the engine, and may suitably be of the shunt wound type or some other type voltage in accordance with the engine speed, and hence energize the solenoid 4| to a degree dependen-t upon the r'ate of engine speed.

The generator 42 is connected through conductors 44 with an adjustable rheostat 45 mounted on the instrument panel `46 of the vehicle. Wires 41 lead from the rheostat to the solenoid 4|. The effectiveness of the solenoid can therefore be controlled by manual manipulation of the rheostat. Alternately, the rheostat could also. be placed in series with the eld of the generator to vary the effectiveness of the solenoid at certain enginespeeds.

The rheostat can eectively be used for quickly and accurately making speed settings, as for example, going from a jurisdiction where the speed limit is 45 miles per hour to one wherein the speed limit is 50 miles per hour. This is accomplished without .aiecting the working of any other part of the apparat The core 43 of the solenoid is connected with the valve 31 and when the solenoid is energized to a predetermined degree,as=when the engine speed attains a certain rate, the valve 31 will be drawn upwardly against the compressive forcev of a spring 48, the tensionA of which is adjustable by a screw-threaded member 50. This upward closing movement of the valve 31 at the higher enginespeeds has the effec-t of closing 01T communicationlthrough the'pipe 33 to the pipe 28, and therefore renders the suctional force Within the pipe 28 more effective to move the throttle valve toward its`closed position. 'I'he extent to which the valve 31 is closed will depend upon the rate of engine speed, and it will be seen that at normal speeds, withthe valve 31 in partly open position, the suctional force within the intake manifold may not be suiilcient to move the piston, but if the engine speed exceeds a predetermined rate, with said suctional condition' existing in the cylinder 21, the valve 31 will be moved toward closed position, thu-s increasing the eiectiveness of the suctional force and causing movement of the throttle valve toward closed position, thereby limiting the engine speed.

pipe 28 and with a valvey sirable cal connection with the `mission of lair through the In order to counteract or overcome any tendency of. the piston 26 to move too quickly upon changes in engine speed, as for example when there distance, I provide means for delaying such movement. Said means comprises a reservoir that has connection past a valve 52 with the cylinder 21. The suction within the intake manifold, when -the engine is running, is usually sufficient to operate the piston 26, if the valve 31 is closed. Therefore, when the valve 31 is closed through increase iny engine speed, to cut oi iiow through the line piston 26 force.

33,- there will be a tendency for the Quick response is not necessary or dewhere there is only momentary change in engine speed. If the operator nds that there is tendency for too quick responsive movement.

by the piston 26, he will open the valve 52 so that some of the suctional force will be temporarily dissipated or reduced by movement of air from the reservoir into the cylinder.

Means are provided for adjustably limiting the length of stroke or movement of the valve 31. so that it can be prevented4 from closing completely and can also be prevented from opening too far. To this .end I provide a threaded extension 53 on the valve andnuts 54 and 55 thereon, that cooperate with a stop member 56 which is carried by the valve chamber. The nut 54 serves to limit downward or opening movement of the valve, and the nut 55 serves to limit closing movement thereof.

An important advantage resulting from .the valve arrangement shown in Fig. 3 is that there is no considerable amount ofi friction. since the valve 31 is loosely mounted in its valvechamber and the small amount of clearance provided between the sides of the valve and the adjacent surfaces of the valve chamber, while preventing appreciable fric-tion, will not permit leakage of sufficient air to interfere with the proper operation of the governor piston 26.

is a change in road grade for a very short to respond instantly to the suctional It will also be seen that since there is no mei 'chanical connection between the core of the sole- `noid 4|, which is responsive to changes in engine speed, and the throttle valve, there will be no appreciable frlctional resistance to the operation of this speed responsive device,.such as would be present in the c-ase of a centrifugal governor directly connected to the throttle valve.

Hence the eifec-tiveness of the speed responsive device will always be the same, at any given speed, regardless of changes in degree of friction between the membersv that have mechanivalve. While there is, of course, some friction as between the valvemoving parts shown in Fig. 2, the suctional force available at theintake manifold is ample to effect proper movement of the throttle valve when the speed governor reduces or shuts off the adpipe 33 to the. cylinder 21.

Referring now to Fie. 4, I show a structure that is similar to that in Fig. 3, in that the solenoid 4| and its associated parts are the same, except that a different form of valve 51 isemployed, said valve being moved toward closed position under increase in engine speed as is the valve 31.

In Fig. 5`I show a centrifugal governor 56, which may be driven from any suitable part of the engine, as for example. the crank shaft or a pump shaft. In vthis arrangement, increase in nor 58 and movement of a camming bar 59 toward the right, thus moving a valve 88 toward its closed position, against .the resistance oi' a spring 8|. In Fig. 6 I show valve-actuating means that is operated through fluid pressure from the water pump or the oil pump 62L of the engine, thereby creating fluid pressure within a line 83 into accordance with engine speeds. The pipe 83 leads into a chamber 64,'-the lower 'side -of which is closed by a diaphragm 85. The diaphragm 85 is connected with a valve stem 86. The valve is normally held in its open position by a spring 81, but. when the pressure in the chamber 64 increases, the valve will be moved downwardly by the diaphragm towards closed position, so as f to restrict or cut ofi' lflow through the pipeI 33 to the suction pipe 28.

My invention has still another advantageous feature, in that fuel mixture can be by-passed around the throttle valve to the intake manifold when the valve is closed, and .the rate of flow of suchby-passed fuel will be controlled by engine speeds. To this end the valve 40 will be closed, whereupon the fuel mixture will flow through the `pipev35, through valve chamber 34 and through pipes 33 and 28 to the intake manifold of Ithe engine. The advantage of this feature is that if air is admitted to4 control the suction in the cylinder 21, this outside air will slightly change the ratio of air and gas mixture, whereas admission of the' fuel mixture between the carburetor and the throttle will just as effec- ,tively operate the device while keeping the ex-A plosive mixture constant.

In Fig. '1 I show another arrangement for effecting energization of the solenoid 4l from the generator 42. In this arrangement the solenoid will not be energized except when the engine and the generator attain a predetermined speed and the voltage therefore reaches a certain value. A relay `89 of the electronic tube type is connected in the circuit, and as is well known in the art, the relay will prevent lcurrent from flowing in the circuituntil the voltage has reached a Y certain value. Other current control devices such as wha-t are known as high pass filters could obviously be substituted for the electronicrelay when it is desired that the solenoid be energized onlywhen the engine attains governing speed.

Referring now to Fig. 8, I show a novel arrangement of foot pedal control for the throttle valve and for the governor. The pedal 10 has at its lower end a hinge connection with the floor'- board of the vehicle, the connection being effected through a rubber block`1l that is carried by the pedal plate and a metalprong or tongue 12 that is secured to the oorboard, the rubber 1I yielding suiiiciently to permit pivotlike movements of the pedal. Near its upper end the pedal engages a link or strut 13 that has pivotal connction with the bell crank lever I4, the bell crank lever in turn having operative connection `with the throttle valve as heretofore explained.

v A latch lever 14 of bell crankform is plvotally n connected to the pedal 10 and has one of its arms hooked for engagement with a keeper 15 that is secured -to the fioorboard of the vehicle, when the pedal is depressed suiliciently far andthe operators foot removed from the arm 16 of the latch lever. A spring 11 yieldably holds the latch lever in hooked engagement a slot being provided in the pedal plate 10 to permit movement of the arm 18 to the dash line 15 position.

with -the keeper 15,

It will sometimes be desirable that the driver should be able to impart a short burst of speed to the vehicle, in excess of that normally permitted by the governor, as when he is already drivingl at approximately the legal limit and it becomes necessary to accelerate the car move'- ment in order to avoid a collision. To this end I provide means actuated by the pedal 10 for rendering the governor ineffective. 'I'his means comprises a valve 18 that admits atmospheric air through'a pipe 18 to the pipe 33 and thence tothe pipe 28, in suiIicient quantity to neutralize or render less effective any suction in the pipe .28. The valve 18 is operated'by a knob 80 on the under side of the pedal, to open the valve against the resistance of a spring 8|, when the pedal is depressed below its normal driving position. The pedal is yieldably restrained against movement below its normal driving position, by engagement of a rubber knob-like projection'82 'on the under side of the pedal, with a rubber block 83 that is mounted onthe fioorboard. Ordinarily the operator will move the pedal down only until he knows -that the rubber 82 has engaged the member 83 and will not exert the additional pressure necessary to move the pedal still further. However, when necessity arises,

he will depress the pedal hard enough to compress the rubber members 82 and 83 suiilciently to permit the boss 80 to push the valve 18 to its open position, and maintain the pedal in such position until the need for excess speed has passed.

As heretofore stated, I am able to automatically effect stabilization of governor control at a predetermined desired engine speed, with a variation of less than 2% from the speed for which the governing apparatus is set. For example,- when the engine is driving the generator 4 2 of Fig. '1 at speeds which render it effective to energiz'e the solenoid 4I, the degree of energization of the solenoidvwill be exactly in accordance. withA or in proportion to engine speeds, since there is no mechanical friction, `and such variations in current flow as result from the use of the electronic relay 83 or a 'high pass filter are inconsequential. As heretofore explained, there is no appreciable friction inthe operation of the valve 31, and this 'is true also of the valve 51.

I claim as my invention:

1. The method of operating an internal combustion engine, which comprises controlling the rate of fuel supply through changes of load conditions as manifested by changes in pressure in the fuel supply line, and automatically changing the degree of control forces exerted by said pres.- sure, in accordance with changes in engine speed.

2. The method of 'operating an internal combustion engine, which comprises controlling the flow of motive fluid to the engine through the use of suctional forces created in the fuel supply line, and automatically changing the said suctonal forces in accordance with changes in engine speed, within a vrange which does not vary more than 2% speed. f

` 3. The combination with an engine having an intake passageway provided with a. throttle valve for. controlling the flow of motive uid to the engine, of means actuated through changes of pressure in the passageway, for imparting movements to the said valve, and means responsive only to changes in engine speed, for varying the force exerted by the manifold pressures upon said pressure-actuated means.

4. 'Ihe combination with an engine having an intake passageway provided with a throttle valve i'or controlling the ow of motive fluid to the engine, of means'actuated through changes of pressure inl the passageway, for imparting movements to the said valve, and means responsive to changes in enginespeed and movable independently of the valve-moving means for varying the force oi' the pressures upon the pressureactuated means.

5. 'I'he combination with an engine having an intake passageway provided with a throttle valve for controlling the ow of motive uid to the engine, of means actuated through changes oi' pressure in the passageway, for imparting movements to the said valve, and means responsive to changes in engine speed for varying the force of the pressures upon the pressure-actuated means, to a degree proportional to variations in engine from` a predetermined engine speed.

6. 'I'he combination with an engine having an intake passageway for controlling the iiow of motive fluid to the engine, of a deviceA actuated by suction from a point in said passageway between the valve and the engine and having operative connection with said valve, and means responsive to changes in engine speed, for changing the degree of suctional force exerted on said device.

7. 'I'he combination with an engine having an intake passageway provided with a throttle valve for controlling the flow of motive iluid tothe engine, of a .device actuated by suction from a point in said passageway between the valve and the engine and having operative connection with said valve, and means responsive to changes in engine speed, and movable independently ofthe throttle valve, for changing the degree of suctlonal force exerted on said device.

8. The combination with an engine having an intake passageway provided with a throttle valve1 for controlling the ow of motive uid to the engine. of a piston having operative connection with said valve, a cylinder for said piston, a suction pipe leading from a point in the passageway between the valve and the engine to said cylinder, and means responsive to changes in engine speed for admitting air to the suction pipe, tov vary the degree oi.' suctional force on the piston.

9. The combination with an engine having an intake passageway and with a throttle and the engine, ofa

valve between the carburetor piston having operative connection with said valve, a cylinder for the' piston,

a suction pipe leading from a point in the passageway between the valve and the engine to said cylinder, a pipe leading from the passageway at a point between the valve and the carburetor to the suction pipe, and means responsive to changes in engine speed, for controlling flow through the second-named pipe to the suction ipe. p 10. The combination with an engine having an intake passageway provided with a throttle valve provided with a throttle valve 'provided with a carburetor` for controlling the ilow of motive uid to the engine, ol.' a manually-operated element operative upon said valve only in the direction to close the same, a spring urging said valve to open position, means actuated through changesof pressure in the passageway', for imparting closing movement to the valve in opposition to said spring, and means responsive to changes in engine speed, for varying the degree oi' pressure exerted upon the pressure-actuated means.

11. The combination with an engine having an intake passageway provided with a throttle valve for controlling the ow of motive uid to .the

engine, of a manually-operated means operative upon said valve only in the direction to close the same, a spring urging said valve to open position, a piston or the like actuated through changes of pressure in the passageway, a valve-moving member operated by said piston, to move the valve toward closed position in opposition to the spring tension, means on said member for moving the valve through a greater distance when the valve is adjacent to its wide-open position than when the valve is at a more nearly closed position', for a given distance oi piston travel, and means responsive to changes in engine speed, for varying the effectiveness of the said pressure upon the piston.

12. The combination with an engine having an intake passageway provided with a throttle valve for controlling the ow of motive fluid to the engine, of a device actuated by suction from a point in said passageway between the valve and the engine and having operative connection with` said valve, a manually-operable element for moving the throttle valve, and means actuated by said element when it is moved to aV predetermined position, 'for rendering said suction device inoperative.

13. The combination with an engine having an intake passageway provided with a -throttle valve for controlling the ow of motive fluid to the engine, of a manually-operated element operative upon said valve only in the direction to close the same, a spring urging said valve to open position, means actuated through changes of pressure in the passageway, for imparting closing movement to the valve means yieldably limiting movement of said element past the position at which it will permit the said spring to open the valve, and means actuated by said element when it is-moved in oppositionto said yieldable means, for rendering said suction device inoperative.

14. The combination with'an engine having an intake passageway provided with a throttle valve for controlling the now of motive iiuid to the engine, .of a piston having operative connection with said valve, a cylinder for said piston, a suction pipe'leading from a point in the passage- Way between the valve and the engine to said cylinder, a valve for admitting air to the suction pipe to vary the eiectiveness of the suctional force on the piston, a solenoid for actuating said valve, and anelectrical generator driven by the engine, for energizing the solenoid to a degree determined by engine speed.

15. The combination with an enginehaving an intake passageway provided with a throttle valve for controlling the ow of motive iiuid to'the engine, of a piston having operative connection with said valve, a cylinder for said piston, a suction pipe leading from a point in the passageway bel tween the valve and the engineto said cylinder,

in opposition to said spring,

a valve for admitting air to the suction pipe to vary the effectiveness of the ,suctional force on the piston, and an electrical device driven by the engine, for actuating the last-named valve, when the engine speed exceeds a predetermined rate.

16. The combination with an engine having an intake passageway provided with a throttle valve i for controlling the ow of motive iluid to the engine, of a piston having operative connection with said valve, a cylinder for said piston, a suction pipe leading from a point in the passageway between the valve and the engine to said cylinder,

in said passageway between the valve and the engine, means operated through changes in pressure in said passageway, for controlling the throttle valve, and avalve actuated upon predetermined changes in the rate of engine speed,

for controlling the iiow of fuel mixture through said line.

18. The combination with an engine having an intake passageway provided with a throttle valve for controlling the flow of motive fluid to the engine, of a device actuated by suction from a point in said passageway between the valve and the engine and having operative connection with said valve, a jdevice movable in response to changes in engine speed, for changing the suctional force on said device. to a degree proportional to variations in engine speed, and means for adjustably limiting the rangeoi movement of ,the last-named device.

19. The combination with an engine having an intake passageway provided with a throttle valve l for controlling the now of motive iiuid to the engine, of a piston having operative connection with said valve, a cylinder for saidpiston, a suc tion pipe leading from a point in the passageway between the valve and the engine to said cylinder, a valve for admitting air to the suction pipe to vary the effectiveness of the suctional lforce on the piston, an electrical device driven by the engine, for actuating the last-named valve when the'engine speed reaches a predetermined rate,

,and means for adjustably controlling the effectiveness of said device at various engine speeds.

20. The combination with an engine having an intake passageway provided with a throttle valve for controlling the iiow oi.' motive iluid to the engine, of means responsive to suction chang'es in the passageway. for imparting movements to the,

valve, a speed device actuated only by changes in engine speed, and a member operated by the .speed device, for modifying the degrees of force exerted through said suction changes.

2l. The combination withan engine having an intake passageway provided with a throttle valve for controlling ilow of motive iluid to the engine and with a governing device which is automatically effective in a predetermined range of engine speed, for controlling now oi the motive uid to the engine, of a manually-operable element for moving the throttle valve, the element being movable from a position at which the valve is' approximately closed, to a position past that at which it admits flow oi' fuel sumcient for full engine power, and means actuated by said element when moved to the last-named position. for rendering the governing device inoperative.-

22. The combination with an engine having an intake passageway provided with a throttle valve for controlling the ilowvo motive fluid to the engine, of a device actuated by suction from a point in said passageway between the valve and the engine and having operative connection with said valve, a manually-operable element for moving the throttle valve from a position at which the valve is approximately closed, to a position past that at which it admits ilow of fuel suiiicient for full engine power, and means actuated by said element when moved to the last-named position, for rendering said suction de'vice inoperative.

GEORGE E. HOWARD. 

